Cytogenetic analyses of Arabidopsis

For a long time, Arabidopsis thaliana was not a favorite of cytogeneticists because of its small chromosomes. Nevertheless, most cytogenetic approaches have become applicable to this model plant during the past decade. Recently, the very small genome, the low content, and strong clustering of repetitive sequences even turned out to be advantageous for the first establishment of chromosome painting in a euploid plant. Chromosome painting together with the high-resolution fluorescence in situ hybridization (FISH) mapping on Arabidopsis pachytene chromosomes has opened new perspectives for plant cytogenetics. In this chapter, we describe standard cytogenetic methods including preparation of chromosomes and chromatin fibers, isolation of interphase nuclei, FISH and immunostaining, painting of Arabidopsis chromosomes, and comparative chromosome painting in other Brassicaceae species.